This is obviously true, a very simple example is the following piece of news: "the most recent vote of the US Senate was 50-48", which not only requires you to look up the actual number, but is also time-dependent.

However, the common usage of "fake news" is not only literally "news that is not true", but rather "news that is deliberately not true in a very specific way".

Many object to the usage of the term itself, and honestly I myself agree that it's not the best way to describe the phenomenon, but it's something that exists regardless of how you choose to call it. I can see the research being useful, I wouldn't say "garbage in, garbage out" really applies here.